04009708 is referenced by 12 patents and cites 6 patents.

A pulse recorder self contained in a wristwatch type case includes a front face having a sweep second hand actuated by an electrical stop watch movement, and a three digit electronic display for the number of pulses counted during the time interval of motion of the second hand. A microphonic or pressure transducer is carried by the back face of the case so as to be pressed into contact with the wrist and is fed to a counter memory driving the display. An initial stop and an angularly moveable stop for the second hand set the time interval for which the hand is to move and provide electrical contacts for enabling the counter only when the hand is in motion.

Title
Pulse rate recorder
Application Number
5/581772
Publication Number
4009708
Application Date
May 29, 1975
Publication Date
March 1, 1977
Inventor
John J Fay Jr
24 Drake Lane, Levittown, 11756
NY, US
Agent
Jack D Slobod
IPC
A61B 5/02
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